This invention relates to an improved acid-containing coated product for the treatment of moist wash in a mechanical clothes drier.
The constant spreading in recent times of the use of automatic clothes driers in commercial laundries and in private households offers the possibility of an after-treatment of the wash simultaneously with the drying, in the clothes drier. Consequently, a number of suggestions have been made how various active substances, mainly those for the softening or antistatic treatment as well as for the scenting of the wash, can be applied to it.
In the sixties, a process was described in the USA for the after-treatment of wash in which flexible substrates impregnated with conventional active substances, for example, absorbent rolls of paper, like those used as paper towels, treated with quaternary ammonium compounds, are placed with the still moist wash in the drum of an automatic clothes drier and the drying process is allowed to take place. During drying, the active substances are transferred to the wash in this process. According to the DE-OS No. 19 65 470, corresponding to U.S. Pat. No. 3,686,025, not every flexible carrier material loaded with textile softeners produces good results.
The suitable flexible substrates must possess a certain adsorption capacity lying within a numerically limited range of from 5.5 to 12. Using a substrate with too low an adsorption capacity causes the active substances to be released too quickly according to the information of this patent, so that the active substances are transferred unevenly to the wash and the treated wash becomes spotted. On the other hand, an adsorption capacity lying above the required area is said to result in the release of too little active substance from the substrate to the wash. Certain absorbent papers, sponges and woven clothes or fleeces are mentioned in this patent application as suitable substrates.
Special softeners and softener combinations also are known that can be combined with flexible substrates that do not have to meet such restrictive requirements with respect to adsorption capacity as those in DE-OS No. 19 65 470. For example, a mixture of a regular cationic textile softener and a fatty acid ester of a polyhydric alcohol at a certain mixing ratio is described in the DE-OS No. 27 00 512, corresponding to British Pat. No. 1,571,527. An agent containing a polyglycerine ester with a fatty acid, as textile softener, is known from the DE-OS No. 27 00 560, corresponding to U.S. Pat. No. 4,214,038. In both instances substrates having adsorption capacities down to 2 can then be employed.
From this state of the art the expert had to deduce that the use of conventional textile softeners, for example, the readily available cationic quaternary ammonium compounds, which are excellent softening and antistatic agents, on substrates with an adsorption capacity lower than the minimum adsorption capacity demanded according to the DE-OS No. 19 65 470 is not possible, or that an uneven transfer of softener and, therefore, spotting of the treated textiles is the result.
In the copending, commonly assigned U.S. patent application Ser. No. 225,761, filed Jan. 18, 1981, now abandoned in favor of its continuation, Ser. No. 416,078, filed Sept. 8, 1982, now abandoned, a product for the treatment of moist wash in a mechanical clothes drier is disclosed consisting essentially of:
(a) a flexible textile sheet of woven, fleece or foam-like structure of a substance selected from the group consisting of polyester, polyamide, polyolefin, polyacrylonitrile, polyurethane, viscose and their mixtures, said flexible textile sheet having an adsorption capacity of from 1.0 to 4.5 coated with PA1 (b) an effective amount for the drier load of wash of an active substance selected from the group consisting of textile softening agents, antistatic substances, fragrances, mixtures of the above and mixtures of the above with nonionic emulsifiers and additives, PA1 (1) cationic quaternary nitrogen compounds having at least one alkyl group having 8 to 26 carbon atoms, PA1 (2) mixtures of said quaternary nitrogen compounds with small amounts of scenting agents, PA1 (3) mixtures of said quaternary nitrogen compounds with up to an equal part by weight of nonionic surface-active compounds, PA1 (4) mixtures of component (3) with small amounts of scenting agents, and PA1 (5) mixtures of any of components (1) to (4) above wherein part of said quaternary nitrogen compound has been replaced by the condensation products of the condensation of 1 mol of a higher fatty acid triglyceride with a mol of a hydroxy-lower alkyl-lower-alkylenediamine or a hydroxy-lower alkylpolylower-alkylene polyamine, in a ratio by weight of from 4:1 to 1:4 of quaternary nitrogen compound to condensation products, PA1 (1) cationic quaternary nitrogen compounds having at least one alkyl group having 8 to 26 carbon atoms, PA1 (2) mixtures of said quaternary nitrogen compounds with small amounts of scenting agents, PA1 (3) mixtures of said quaternary nitrogen compounds with up to an equal part by weight of nonionic surface-active compounds, PA1 (4) mixtures of component (3) with small amounts of scenting agents, and PA1 (5) mixtures of any of components (1) to (4) above wherein part of said quaternary nitrogen compound has been replaced by the condensation products of the condensation of 1 mol of a higher fatty acid triglyceride with a mol of a hydroxy-lower alkyl-lower-alkylenediamine or a hydroxy-lower alkylpolylower-alkylene polyamine, in a ratio by weight of from 4:1 to 1:4 of quaternary nitrogen compound to condensation products,
particularly where said textile softening agents and antistatic substances are selected from the group consisting of quarternary nitrogen compounds derived from ammonia or imidazoline and having from 1 to 2 long chain hydrocarbyl groups with from 8 to 26 carbon atoms and mixtures of said quaternary nitrogen compounds with up to 80% by weight of the mixture of the condensation product of a higher fatty acid triglyceride with a hydroxy lower alkylpolyamine.
With the substances according to the teachings of the above patent application Ser. No. 225,761, final treatment products for laundry were made available that are derived from substrates with very low adsorption capacity and with the use of known quaternary ammonium compounds derived from ammonia or imidazoline, which are used on a large scale as textile softeners because of their excellent effectiveness. These products do not cause spotting on the laundry when used in the clothes dryer. According to the teaching of the DE-OS No. 19 65 470, spots of irregularly transferred textile softener would have had to be noticed on the laundry with the use of substances with substrates with an adsorption capacity below 5.5. It is known from other patents in the literature that other substances than the usual, highly effective quaternary ammonium compounds must be used as textile softeners, when substrates with an adsorption capacity of less than 5.5 (or more than 12) are desired for use. (See, for example, the German published Application Nos. 27 00 512, 27 00 560; British Pat. No. 1,549,432 and U.S. Pat. Nos. 3,989,631 4,022,938 4,025,444 4,049,858 4,055,248 4,073,996 4,076,633 4,085,052 4,096,071 4,103,047 4,110,498 4,121,009 4,142,978.
Unfortunately, however, the products of Ser. No. 225,761 occasionally will undergo yellowing if kept for a relatively long time.